Slack adjuster



July 21, 1931.

W. O. MARTIN SLACK ADJUSTER Filed Aug. 26. 1929 5 Sheets-Sheet l INVNTORV AHORN EY July 21, 1931. w, o. MARTIN 1,815,859

sLAcx ADJUsTER I 'Filed Aug. 26. 1929 s sheets-sheet 2 INVENTOR BY Z To.-

ATTORN EY w. O. MARTIN SLACK ADJUSTER July 21, 1931.

FigedAug. 2e, '1929 s sheets-sheet :s

WITNESS connected to the live cylinder lever k.8, as is customary. It will thus be .seen that the brakes 4 may be voperated either manually through the means 9 or by air-pressure by yvirtue of the air pipe connections 15. f

It should be noted that' the floating lever..

11 is notidirectly fulcrumed'uponthe framing of the carl, but is pivotally connected to my slack'adjuster, which will nowv be described.. y r

' ReferenceV is now made to`Figure`s2 andv 3,

wherein it will be seen thatmyadjuster comprisesa casting 16 of elongated form, having! side walls 17andsupporting flanges 18,5and p The an end wall19 forming a bearing 19. wallsy 17 'each have a. slot 20 v extending throughout "the major yportion Vof 'the walls 17, as clearly shownin Figure 2, adapted to v,receive a` sliding ful'crum 21, as will be described hereinafter.l i'

i Adjacent the closedend 19 of the casting 16, there v'is provided'a diagonally extending bearing 22,7and slightly to the rearthereof and extended downwardly and'odset toV one side of the bearing-22-there is an arm 23, adapted to afford a seat for a spring tension means. j

` Journalled within the bearing 19` there is Y ascrew-threaded shaft 24 which' is threadedly engaged in. the cross-head 26Vof the sliding fulcr'um 21. ',The cross-head 26 has laterally extending bearing armsf27, adapted for slid-V Ving engagement within the slots 20, as shown.

" VThe shaft 24 has a worm gear 28 lined thereon snugly abutting the'endv 19'o`f`the ,Cas'ti'ng. rlhe shaft 24 maybe secured in 1 proper position by a pinl 219,closely adjacent Y Ythe bearing 19.1

The sliding fulcrumf21is aperturedfor' 46T pivotal connection tothe floating leverll, as 1 at 30,'in Figures 1 and 2.

Attention is now directed to Figure 22,

lwherein it willbe noted that the arm' 22V has v "afbea'ring 31 at its entremitydisposedin a, vertical medialV line jwith1thegearf28, and 1 within this Ybearing,there lis revolublymount- A' ed aftransverse shaft-32, having keyed'therei- Y, mounted a tubular shaft 35,1which has an;

on a worm screw 33 adapted to meshw/thn Y the worm' gear 28. f The worm screw f33fpref- :lateralmovem'ent of the shaft, which might fotherwiserroccur, and` upon the opposite iside'V 4ofthe bearing, I provide a ratchet gearf34v erably abuts the bearing31v andthus prevents suitably-splined upon the Ashaft 32, as Show',V in Figuref' z v v .t

Upon that portion, ortheshaa se mena. ing beyond the gear 34 there is swingably operating lever 36 anda pawl-supp o'rtingV Vilever V37. Thelever .36 is extended*ido-wn` wardly and is connectedtofa'link 3.8 extended rearwardly beneaththe casting 16.1 The f rearwardlyy extendingportion of the link Y. is slidably supported by al pistonfoperated lever rkThe lever l40, in the .presentinwof which lthere is pivotallymounted :a pawl l46 adaptedtoengage the teethfoflthe ratchet l.wheel 34. In order to holdthe pawl46 in f engagement Vwith the :teeth of the ratchet wheel-34', the'low'erportion of the arm 37 is cuppejdftofreceive one end of a tension The other end of the springi47 isiretained within a housing 48 formedfupon the lower/end ofthe arm 23, asclearly shown in Eigures 3 and 7. The tension ofthe spring- 47 ymaybe varied by `1nanipulation of the adjusting screw/.49.H Y o Y 'j Y Fromv the foregoing, it will be readily Tap;` parent `that my slack adjuster may be readily incorporated with any of thel well` known brake riggings, by merelyremoving the usual fulcruln bracketsupporting the floating lever 11 and substituting -Iny .adjusting device 16,

the connections thereto being madeas de'-V scribed.y Y ,j

l With my devic'einstalled upon ar cara-nd it is desiredto adjust the vslack in the brake rig"-` ging the shaft 32 is rotated, from yeither Side of the car, until all-slackis taken 4out 4of the brake rigging, and the' brake shoes 4 fit snugfly'V against the wheelsrg3. This reduction of slack kis'b'rought about inthe following man! ner :-'-As the shaft v32y is rotated, therwo'rmv screw.V 33' isy likewise rotated. which fi-n turn rotates'the lwormg'ear 28, and since the gear 28 is keyed, uponV the screw-,threaded shaft 24,

this shaft isl consequently rotated, and due to-s'uch rotation,`the crojssheadV 26 is moved' longitudinally within-the'jslotsZQ,resulting in movement of the.brakeirigging/as will be apparenti. With the'brakes'hoes snugly engagingthe wheels, thfezpawl 46 -israised to release the ratchet' wheel. '34, whereupon ythe shaft ,'32 is rotated; tol lproduce af slack in the brake rigging lcor'ijespo'nding tY the amount of standing pistn travel.' Thepawl 46 may now be released so "asftopag'ain'engagethe' ratchet wheel. ,j

1,813,852; ,i f Yif t To automatically maintainfapredeter-l Y fmined running piston travel, the nut 44is ad=Y justed upon the link 38, so'thatfthe distance betweenfthe adjustingv nut V44 and tripf39 is equal to the distance ofa vpredeterifniried run! "ning .piston travel, less-onehalfinch, which is allowed for lost motion'and'thelike.: As an, illustration, itA isY rvdesired to maintainfauto# matically, an 8-inoh running pistontravel,v

VTheadjusting' ynut44 isis'pa'c'ed seven and one;-k l

half'inchesffroln'theltripis),- gli I Fe-m te@ fregenalmeeneem ofoiydea A shafts and in mesh with each other, .a hollow shaft swingably mounted onsaid transverse shaft, means ,forA swinging said hollow shaft, Y lmeansforrotatingsaid transverse Yshaft upon swinging of saidv hollow ishaft, Vand separate I means for rotatingnsaid transverse shaft for longitudinal movement fof, saidv brake Vlever fulcrum, independent-ly of said other named v v 1' Y means.` y v l f f 10 A 5, The combination ,ofr a.V pair of trucks,

brakerigging associated with each of saidV Y "trucks comprising. anoperating link, a float- .ing lever connectednto each'of said 'operating Y' 'f' links, arlink connection between saidfloating 15 levers,la brake cylinder havingv a reciprocating piston, said piston beingconnected to one of said floating levers,a movable fulcrum con- Y nected to one of said other floating ylevers and havings,a:screwthreaded aperture, means 'for 7 20 vmo'vingsaid ful'crui'n including va transverse c* shaft, asecond shaft operativelyassociated f withsaidtransverse shaft for rotation thereof, saidshaft having 'a'screw threaded portion engaged-inthe screw threaded aperture of Y 2 5 y.said fulcrum, Van'dmeans connected between said piston andsaid transverse shaftfor rotating said shaftupon travel of'said piston beyond la predetermined distance to automatically'compensate for slack in said brake 

